The invention relates generally to the field of media control in inkjet printers, and more particularly to post printing media control.
It is important in inkjet printing to provide media control in the vicinity of the print zone in order to hold the media in a proper position while drops of ink are applied by the printhead. In the past, a plurality of large diameter (approximately 12 mm) individual spring-loaded starwheels were used opposite slip/drive exit rollers in order to prevent media buckling en route to an output tray. Such large diameter individual starwheels were used in the Hewlett-Packard PaintJet XL color inkjet printer. Such individual starwheels were reasonably satisfactory for 180 dpi (dots per inch) printheads, so long as the pressure applied by the exit rollers/starwheels to the newly printed media therebetween was rather low, typically less than 0.1 Newtons. However, when higher density 300 dpi printheads were used along with heaters, greater advance accuracy was required of the exit roller. Larger forces were used, creating the risk of the starwheel teeth damaging the newly printed media, particularly when used with exit rollers that acted as tension drive rollers to keep the media taut in the print zone and pull it into the output tray.